• 광물과 암석
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• 제34권3호
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• pp.193-208
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• 2021

거창화강암에서 발달하는 여섯 방향의 결(H2~R1)과 관련된 미세균열의 길이(①), 미세균열의 간격(②) 및 압열인장강도(③)의 특성을 분석하였다. 첫째, 결의 고유한 특성을 반영하는 위의 세 주요 인자에 대한 18개의 누적 그래프를 작성하였다. 세 면 및 세 결로 분류한 이들 그래프에 대한 종합 도면을 통하여, 길이, 간격 및 압열인장강도에 대한 28개의 파라미터를 결정하였다. 이들 파라미터 사이의 상관성 분석의 결과는 다음과 같다. 둘째, 위의 파라미터는 세 결 및 세 면 사이의 파라미터 값의 크기에 대한 정렬순서에 따라 여섯 그룹(I~VI)으로 분류하였다. 그룹 I 및 II에 속하는 파라미터의 값은 R(1번 결) < G(2번 결) < H(3번 결) 및 H2, 𝚫s, 𝚫L 및 oS^mean), 지수(λ_L^mean 및 λ_S^mean), 기울기(a^mean) 그리고 이방성 계수(An^mean)에 대한 8개의 파라미터의 값은 R < G < H 그리고 H'(3번 면) < G'(2번 면) < R'(1번 면)의 순이다. 셋째, 세 면과 세 결 사이의 분포 형태에 있어서 주목할 만한 차이점은 다음과 같다. 세 면에 대한 도면으로부터, 두 적합선이 X축 상에서 만나는 두 점 사이의 거리에 해당하는 𝚫L, 𝚫s 및 𝚫σ_t의 값은 R' < H' < G'의 순으로 증가한다. 특히, 길이 및 압열인장강도와 관련된 R2 및 G2의 두 그래프는 서로 거의 평행하며 3번 면의 특성을 보여준다. 압열인장강도와 관련된 그래프 중에서, 3번 면에 대한 전체적인 모양은 2번 결의 전체적인 모양과 유사하다. 세 결에 대한 도면으로부터, 길이와 관련된 그래프의 기울기는 R

• 환경영향평가
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• 제29권4호
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• pp.272-285
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• 2020

본 연구에서는 3차원 기상 및 대기질 모델의 입출력 자료를 평가하는 데 필요한 통계 검증지표를 선별하고, 선정된 검증지표의 기준치를 조사하여 그 결과를 요약하였다. 여러 국내외 문헌과 최근 논문 검토를 통해 최종 선정된 통계 검증지표는 MB (Mean Bias), ME (Mean Error), MNB (Mean Normalized Bias Error), MNE (Mean Absolute Gross Error), RMSE (Root Mean Square Error), IOA (Index of Agreement), R (Correlation Coefficient), FE (Fractional Error), FB (Fractional Bias)로 총 9가지이며, 국내외 문헌을 통해 그 기준치를 확인하였다. 그 결과, 기상모델의 경우 대부분 MB와 ME가 주요 지표로 사용되어 왔고, 대기질 모델 결과는 NMB와 NME 지표가 주로 사용되었으며, 그 기준치의 차이를 분석하였다. 아울러 이들 통계 검증지표값을 이용하여 모델 예측 결과를 효과적으로 비교하기 위한 표출 도식으로 축구 도식, 테일러 도식, Q-Q (Quantile-Quantile) 도식의 장단점을 분석하였다. 나아가 본 연구 결과를 기반으로 우리나라의 산악지역의 특수성 등이 잘 고려된 통계 검증지표의 기준치 설정 등의 추가연구가 효과적으로 진행될 수 있기를 기대한다.

• 말소리와 음성과학
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• 제4권2호
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• pp.89-94
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• 2012

The aim of this study is to investigate the usefulness of the parameter CPP (cepstral peak prominence) and LTAS (long term average spectrum) band energy for an analysis of breathy voice with vocal fold paralysis. Thirty-four female subjects who have vocal paralysis after thyroidectomy participated in this study. According to the perceptual judgements by three speech pathologists and one phonetic scholar, subjects were divided into two groups: breathy voice group (n = 21) and non-breathy voice group (n = 13). Maximum sustained phonation task was measured for acoustic analysis. CPP-related (i.e. mean F0, mean CPP, and mean CPPs) and LTAS-related (i.e. minimum, maximum, and mean) parameters were used. Independent samples t-test was conducted. Regarding CPP, there are significant differences in mean CPP and mean CPPs between groups. The values of mean CPP and CPPs in the non-breathy voice group are higher than those in the breathy voice group. The CPP could be regarded as the useful parameter for breathy voice analysis in the clinic. When it comes to LTAS, energy from 0 to 2 kHz are significantly different between groups. The minimum value of non-breathy group is lower than that of breathy group, whereas the maximum value of non-breathy group is higher. The frequency band below 2 kHz seems to be related to breathy voice.

• 설비공학논문집
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• 제16권12호
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• pp.1140-1148
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• 2004

Recently the Predicted Mean Vote (PMV) has been used as an important index to evaluate the degree of the indoor thermal comfort in modern residential buildings. It is known that the PMV is mainly affected by four major factors, which are the air temperature, the air velocity, the humidity and the mean radiant temperature (MRT). Through the numerical calculation of the temperature and the modeling of the mean radiant temperature considering the solar radiation, we proposed the new modeling strategies of the mean radiant temperature and investigated the PMV index and evaluated the MRT. Also, we compared the numerical results with the experimental values. As the results, we found out that the MRT is affected by the wall temperature and the solar radiation. We also knew that the new modeling strategies of the mean radiant temperature is a more correct way of PMV calculation. Especially, the new modeling is necessary for the spaces like an atrium and large rooms with windows mainly influenced by solar radiation.

• 자동차안전학회지
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• 제15권1호
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• pp.55-62
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• 2023

In this study, a chest deflection is predicted by introducing a deep learning technique with the results of the frontal impact of the USNCAP conducted for 110 car models from MY2018 to MY2020. The 120 data are divided into training data and test data, and the training data is divided into training data and validation data to determine the hyperparameters. In this process, the deceleration data of each vehicle is averaged in units of 10 ms from crash pulses measured up to 100 ms. The performance of the deep learning model is measured by the indices of the mean squared error and the mean absolute error on the test data. A DNN (Deep Neural Network) model can give different predictions for the same hyperparameter values at every run. Considering this, the mean and standard deviation of the MSE (Mean Squared Error) and the MAE (Mean Absolute Error) are calculated. In addition, the deep learning model performance according to the inclusion of CVW (Curb Vehicle Weight) is also reviewed.

• Geomechanics and Engineering
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• 제34권5호
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• pp.547-559
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• 2023

We evaluated the applicability of machine learning techniques and the Kuz-Ram model for predicting the mean fragmentation size in open-pit mines. The characteristics of the in-situ rock considered here were uniaxial compressive strength, tensile strength, rock factor, and mean in-situ block size. Seventy field datasets that included these characteristics were collected to predict the mean fragmentation size. Deep neural network, support vector machine, and extreme gradient boosting (XGBoost) models were trained using the data. The performance was evaluated using the root mean squared error (RMSE) and the coefficient of determination (r²). The XGBoost model had the smallest RMSE and the highest r² value compared with the other models. Additionally, when analyzing the error rate between the measured and predicted values, XGBoost had the lowest error rate. When the Kuz-Ram model was applied, low accuracy was observed owing to the differences in the characteristics of data used for model development. Consequently, the proposed XGBoost model predicted the mean fragmentation size more accurately than other models. If its performance is improved by securing sufficient data in the future, it will be useful for improving the blasting efficiency at the target site.

• Journal of Chest Surgery
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• 제13권4호
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• pp.364-374
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• 1980

Twenty-two patients were selected for evaluation of pre-and postoperative pulmonary function. These patients were performed open cardiac surgery with the extracorporeal circulation from March 1979 to July 1980 at the Department of Thoracic and Cardiovascular Surgery, Kyungbook National University Hospital. Patients were classified with ventricular septal defect 5 cases, atrial septal defect 5 cases, tetralogy of Fallot 5 cases, mitral stenosis 4 cases, rupture of aneurysm of sinus Valsalva 1 case, left atrial myxoma I case, and aortic insufficiency 1 case. The pulmonary function tests were performed and listed: [1] respiratory rate, tidal volume [TV], and minute volume[MV], [2] forced vital capacity [FVC] and forced expiratory volume[FEV 0.5 & FEV 1.0], [3] forced expiratory flow [FEF 200-1200 ml & FEF 25-75%]. [4] Maximal voluntary ventilation [MVV], [5] residual volume [RV] and functional residual capacity[FRC], measured by a helium dilution technique. Respiratory rate increased during the early postoperative days and tidal volume decreased significantly. These values returned to the preoperative levels after postoperative 5-6 days. Minute volume decreased slightly, but essentially unchanged. Preoperative mean values of the forced vital capacity, functional residual capacity and total lung capacity decreased [63.2%, 87.2% & 77.3% predicted, respectively], and early postoperatively these values decreased further [19.6%, 76.0% & 38.0% predicted], but later progressively increased to the preoperative levels. In residual volume, there was no decline in the preoperative mean values [100.9% predicted] and postoperatively the value rather increased [106.3-161.7% predicted]. Forced expiratory volume [FEV 0.5 & FEV 1.0] and forced expiratory flow [FEF 200-1200 ml & FEF 25-75%] also revealed significant declines in the early postoperative period. There was no significant difference in values of the spirometric pulmonary function tests, such as FEF 1.O and FEF 25-75% between successful weaning group [17 cases] extubated within 24 hrs post-operatively and unsuccessful weaning group [5 cases] extubated beyond 24 hrs. Static compliance and airway resistance measured for the two cases during assisted ventilation, however, any information was not obtained. Long term follow-up pulmonary function studies were carried out for 8 cases in 9 months post-operatively. All of the results returned to the pre-operative or to normal predicted levels except FVC, FEV 1.0, and FEF 25-75% those showed minimal declines compared to the pre-operative figures.

• Ocean Science Journal
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• 제42권4호
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• pp.211-222
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• 2007

We compare insolation results calculated from two well-known empirical formulas (Socket and Beaudry's SB73 formula and the original Smithsonian (SMS) formula) and a radiative transfer model using input data predicted from meteorological weather-forecast models, and review the accuracy of each method. Comparison of annual mean daily irradiance values for clear-sky conditions between the two formulas shows that, relative to the SMS, the SB73 underestimates spring values by 9 W $m^{-2}$ in the northern Adriatic Sea, although overall there is a good agreement between the annual results calculated with the two formulas. We also elucidate the effect on SMS of changing the 'Sun-Earth distance factor (f)', a parameter which is commonly assumed to be constant in the oceanographic context. Results show that the mean daily solar radiation for clear-sky conditions in the northern Adriatic Sea can be reduced as much as 12 W $m^{-2}$ during summer due to a decrease in the f value. Lastly, surface irradiance values calculated from a simple radiative transfer model (GM02) for clear-sky conditions are compared to those from SB73 and SMS. Comparison with iu situ data in the northern Adriatic Sea shows that the GM02 estimate gives more realistic surface irradiance values than SMS, particularly during summer. Additionally, irradiance values calculated by GM02 using the buoy meteorological fields and ECMWF (The European Centre for Medium Range Weather Forecasts) meteorological data show the suitability of the ECMWF data usage. Through tests of GM02 sensitivity to key regional meteorological factors, we explore the main factors contributing significantly to a reduction in summertime solar irradiance in the Adriatic Sea.

• 대한수의학회지
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• 제29권3호
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• pp.333-342
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• 1989

Effect of raising types and environmental conditions on the infection of Toxoplasma in the swine, the cat and the man were studied in Cheju Island from Sept. 1987 to Aug. 1988. Blood samples were taken from 214 conventionally raised swine in 6 villages and 506 swine raised in swine specialized farms, 122 cats raised under free moving or restraned conditions in 8 locations, 113 butchers, and 210 villagers. Toxoplasma antibody values of the blood sera were determined using the enzymelinked immunosorbent assay (ELISA). The eating type of viscera was also investigated by using questionaires 1. When ELISA method was used, the percentage of Toxoplasma infected swine among the conventionally raised and of those raised in swine specialized farms were 60.7% and 21. 390, respectively. The respective mean of antibody values (${\pm}SD$) were 0.589 (${\pm}0.310$) and 0.385 (${\pm}0.237$) and differed very significantly (p<0.01). A significant difference was also found in antibody values among 6 villages (p<0.05). 2. The mean infection percentage of toxoplasma in the cat was 38.2%. the infection percentage for cats raised under free-moving and re~;trained condition were 37.0% and 38.2% respectively. The respective antibody values(${\pm}SD$) for toxoplasma were 0.600(${\pm}0.614$) and 0.637 (0.645), and did not difference significantly. 3. The infection percentage of toxoplasma in villagers and butchers were 26.2 and 38.3% respectively. The respective antibody values (SD) for toxoplasma were 0.429(${\pm}0.195$) and 0.341 (${\pm}0.236$), and differed very significantly (p<0.01). There were also highly significant differences Pyo-sun and other village (p<0.01). 4. Analysis of the questionaires showed that 26.0% of 392 villages eated liver and some villagers eated other viscera.

• Journal of Pharmaceutical Investigation
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• 제33권1호
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• pp.51-53
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• 2003

This study was conducted to compare the bioavailability of a generic product of Sinil Atenolol Tablets (Sinil Pharmaceutical Co., Ltd., Korea) with the innovator product, $Tenormin^{\circledR}$ Tablets in 20 healthy Korean volunteers. The volunteers received a single 50 mg dose of each atenolol formulation according to a randomized, two-way crossover design. Plasma samples were obtained over a 24-hour interval, and atenolol concentrations were determined by HPLC with a fluorescence detector. From the plasma atenolol concentration vs time curves, the following parameters were compared: area under the plasma concentration-time curve (AUC), peak plasma concentration $(C_{max})$, time to reach peak plasma concentration $(T_{max})$, and terminal first order elimination half-life $(t_{1/2})$. No statistically significant difference was obtained between the $T_{max}$ values, and the logarithmic transformed AUC and $C_{max}$ values of the two products. The 90% confidence for the ratio of the logarithmically transformed AUC and $C_{max}$ values of Sinil Atenolol Tablets over those of $Tenormin^{\circledR}$ Tablets were calculated to be between 0.99 and 1.07, and 1.04 and 1.16, respectively; both were within the bioequivalence limit of 0.80-1.25. The mean of $T_{max}$ in $Tenormin^{\circledR}$ Tablet group was 3.68 hour, and that in Sinil Atenolol Tablet group was 3.65 hour. The values of $t_{1/2}$ between the two products were found comparable, and the mean $t_{1/2}$ values of $Tenormin^{\circledR}$ Tablets and Sinil Atenolol Tablets were 5.9 and 6.0 hour, respectively. Based on these results, it was concluded that Sinil Atenolol Tablets were comparable to $Tenormin^{\circledR}$ Tablets in both the rate and extent of absorption, indicating that Sinil Atenolol Tablets were bioequivalent to the reference product, $Tenormin^{\circledR}$ Tablets